The long-term objective of this project is to better understand the neurobiological and metabolic consequences of phencyclidine (PCP) abuse. Acute use of PCP has been shown to produce violent, self-destructive and psychotic behavior, and in some chronic users a long-term schizophrenia. The specific aims of this project are designed to test the hypothesis that PCP metabolites can lead to long term, detrimental effects through irreversibly binding to critical macromolecules in the central nervous system and at peripheral sites. For these studies, an animal model is being developed to provide a source of tissues for in vitro studies of the mechanism(s) underlying vulnerability to PCP metabolite covalent binding. These in vitro experiments will permit studies of specific isoenzyme pathways and other potential targets of covalent binding in normal animals and in animals which are genetically deficient in the isoenzyme pathway responsible for generating the electrophillic metabolites. Covalent binding to specific isoenzymes and other proteins will be assessed using a series of complimentary biochemical, immunochemical and physical/chemical methodologies. Together, these techniques will allow characterization of metabolite covalent binding in tissue sections, isolated proteins, and peptide fragments. In other studies, the consequences of irreversible PCP metabolite binding will be studied by measuring the changes in function of specific metabolic pathways in normal animals, PCP chronically dosed animals and genetically deficient animals. Finally, the neurobiological consequences of PCP metabolite covalent binding will be assessed through immunohistochemical localization of the covalent binding sites in the central nervous system and a series of ligand binding studies using brain homogenates and partially purified receptors from normal and PCP chronically dosed animals. Together, these data should allow us to better predict the consequences of PCP metabolite covalent binding of PCP metabolites could lead to a better understanding of the long-term neurobiological consequences of PCP abuse and elucidate mechanisms through which certain individuals might be particularly susceptible.